This materials characterization study of ceramics from an archaeological site in coastal Virginia is designed to produce information concerning Tidewater Algonquian exchange patterns during the Woodland Period (1000 BCE -- 1600 CE). X-ray fluorescence spectrometry (XRF), which uses X-ray technology to determine the chemical make-up of a sample, allows the comparison of the elemental composition of ceramics from the Kiskiak site to the composition of ceramics from other sites and of clay sources throughout Virginia. Changes in the proportion of local to non-local ceramics over time provide evidence critical for evaluating which of two competing models most aptly describes exchange systems during the transition to agriculture and sedentism in the Chesapeake. This analysis links methods drawn from physics, chemistry, and geology to questions concerning Native social histories and is an example of archaeometric approaches rarely employed in the Chesapeake.